1. Field of the Invention
This invention pertains to a non-rigid composite sheet having fire resistant properties. The sheet is useful as walls in a cargo container, particularly containers used in aircraft.
2. Description of Related Art
Cargo containers or unitary load devices (ULDs) are used in aircraft, ships, road vehicles and railcars to carry goods. For economic reasons there is a desire to reduce the weight of an empty container while minimizing its operational cost. Shipment of flammable materials in air cargo containers is creating a serious safety issue for airlines and air cargo carriers. There is increasing concern about the capability of existing containers to contain the spread of fire when the ignition source is the cargo itself. An example of such an ignition source is a lithium-ion battery. Consequently, to prevent possible human casualties and cargo equipment losses, airlines and air cargo carriers are looking for flame resistant cargo containers to contain fires that may originate within the containers. A tightening of regulatory requirements is expected over the next few years. There is therefore a need to provide a light weight cargo container having enhanced capability to contain the spread of fire from within the container that meet stringent durability standards while providing an extended lifetime with minimum maintenance.
U.S. Pat. No. 8,292,027 to Richardson et al describes a composite laminate comprising in order (a) a flame retardant polymeric moisture barrier (b) an inorganic platelet layer and (c) a flame retardant thermoplastic film layer.